1,5-Bis-(1,4-benzodioxin-2-yl)-3-azapentan-1,5-dioles having .beta.-adrenergic blocking agents have been described in J. Med. Chem. 13, (2), 169-176 (1970) and specific stereochemically isomeric forms of said 1,5-dioles have been described in U.S. Pat. Nos. 4,380,653 and 4,313,955.
The compounds of the present invention differ from the said prior art compounds by the replacement of one oxygen atom in the benzodioxane ring by a direct bond or an optionally substituted methylene moiety and by their increased .beta.-adrenergic blocking activity.